As long as the maths operations are close together the compiler will be able to optimise this to the best executable instructions. If you have access to offline compilers and really care about the expense, it may be worth comparing the cost of x=(x+20)/220 vs x=(x/220)+(20/220). {Some GPUs can fold two maths operations into a single cycle.} If you haven't, don't worry, just go with the simple version, it'll be fine.